Control unit for electrical instrumentalities



March 13, 1956 GEBEL 2,737,826

CONTROL UNIT FOR ELECTRICAL INSTRUMENTALITIES 2 Sheets-Sheet 1 FiledFeb. 14, 1955 .mww

3, jrvmg G'ebal 7 March 13, 1956 1. GEBEL 2,737,826

CONTROL UNIT FOR ELECTRICAL INSTRUMENTALITIES Filed Feb. 14, 1955 2Sheets-Sheet 2 jmdwgm) Irvzpg E'ebnZ United States Patent-O 2,731,826-CGN'IRQLUNI'I FOR ELECTRICAL INSTRUMENTALITIES G'ebe t Q s ar l-gas lgnor to. or ngi Prod cts Corporation, schillerlark, 111., a corporationof Dela-v were Ahplk fiim Februa y 1 19 Ser a N t-437,33

portionvoi the term: of {the patent from Jan ary 24, p.12-13,;- h sheen,ssl imedand dedicated to the Public I BClaims; (Cl. 74-527) applicationis in part adivision-ofi the copending joint app ication of Edgarnlti.S'orehgand Irvinv Gebel, NQaZQiififl'Elz, filed July-"14,; 19 -52,- nowPatent No; 2 7%,564 iQSHEdUQCtQbEF 11,: 19551 and it is also a: con:tinuat-ien .Qfi part of:v my later copending application Se No.,- 403755.,- filedlanuary 13', 1954';

The earlierofa said. eopending rapplicationsrelates to aflnidpressureoperated switch and the control device herein isclosedforreghhtingathe: operating characteristicsvofthe switch: constitutesthe main. embodiment of= the invention presented in this application Thelater of said copending applications: discloses a modifiedfversioni oicontrol device; and; the v part of the inventiolt p ie'sented inthis;application concerns? features of said modified control device which areclosely related tix those, of; the control device; of? said-joint:application.

Elnid pressure operated switchesofi the type herein-re to areparticularly usefiul in automatic washing mah nes;;a1though1 theirutility is by' no: means: restricted to; such device's Since;their-applieationi to automatic washing n ne s best illustrates: themanner on their use-,1 the: pre ;e operated, switch and especially thecontrol meansthereiflr" be; described with. particular ref erence toaninstallatiomin; a washing-machine; and spa cifically with referenceto: the; manner: in; which thecon trol mean j-QlI-lPlOYfidtO.adjustabl'y' predetermine the volume-of washing liquor or'water tobepdeliveredtinto of a washingpmachine-int one-instance, KSE-WGH as; toregulate:theytempe ieture of the water thus-(le li t n d t he t ano herinstance;

, In most auto .t to wash ng ma h es pr y hruse; machinefilled-withwater through? two water-lines; one, connectin -,1 with asourcesot holt; Water and rthe other wil ltaaso lrce QfyQQld; water;electromagnetic valve in each of lthese water Supply lines; mustt beopenedttotad mi ateninto h m chines nd i is-;.custom y* 'p vide: atemperature control switch; instrumentality" to enable,- selection ontheT desired temperature of the water s tt ill he machine.

for; instance; henit isde ired; to; fill; the; machine with hot; water,the-temp rature: elect grswitch manue: 31131 r set to efiectenergizat-ion: and opening 0f only the electromagnetic valve in the'hotwater=1ine, ;and:-the; tub of the machine will fill with hot water; toayprede'termined' evel mfin y t p ss e perated watch-level switch,vgoverning; energization of both 015-, said olefin-0+: magnetic valvesThe. level control switch is; opened: automatically at the time water ofthe desired; temperaturereaches a predetermined; level the tub of themac chineto eiiect deenergization and; closure: of thevelect'rosmagnetic valve intthe hot water line A similar procedure isfollowedivwhen; it: is desired to; fi l he m chine i h o d w r, t b ingun s o d: that the tempe iatu're selecting switch is, adjustedanoptexam: of the machine to ffe e si a i nt nd op n-ins of ohl'y' theelectromagnetic valve in the cold; waten-linet; It i s ed. o. ille ma hn h. warm; wa r; hetemperattire, sel tins. switch is manually aditistedo 2,737,826 Patented Mar. 13, 1956 2 v eifect' simultaneousenergizationand opening of both electromagneticvalves to allow hot and cold water together to enter the machine In a washing machine of the type hereinreferred to, it-1is: also desirable: toprovide: for automatic filling ofthe machine; to any one of anumber of differentlevels' so" that a savingof hot water cantbe effected when: it is do siredto wash smaller thanaverage loads of clothes. This feature has been realized in the pastby-thep'rovi' siona of -anial'iually adjustable stationary contact inthep'ressure openatedswitch, to; allow presetting-of said stationarycontact toone o'r more positions representing dif' ferent. water levels.for the machine.

It is an object of the present invention to provide a HQVQI? controlunit? for pressure operated'switch'es of the character described whichfacilitates adjustment of the stationary contact to, any ot a number ofdifferent posi -t tionsrepreseming different water levels for the;machine.

More speeifically this invention has as its objectthe "on ofi a controlunit: ,of' the character described embodies a manuallyzrotata-ble; shaftfor elfecte ing adjustment of the stationary contact of a pressureswitchprthe like, has a simple and inexpensiveind gmech isrniorarrestingrotation-of thecontrolshait, at any-of; a numberofipredetermined positions, rep-.- tes ntinstdi i rent posi ions of;adiustnieut of the stati narxi ontac t a a In this; respect,, i:isavfprther object of this invention o prov de ac ntro z uniti of; thecharateerdescribed with acamrfi ed the ontrol shait of the unit, oneperipha ra p r -meet he ca e ng oonerahl'e with n adjusts abl'e elemen fan: a so i ins rumen ality toetfect a h nge in t1ie p s t Qn of sa dadjustable element in con seqi enseot rota ion; t ontr l; haf an anoth rpieplt r porti n of sa d am being p rable with-:a dent. fin e on he: otrol-1 t re t r ta ions fs the cam at any of, a,nnmher of difierentpositionsof adjusteme t of. said adjustableaelernent.

St ll no herip rposeof; his inven i n resides in the. nrovisionuofia ntrl unittof the hara er descri ed 111 has. the combined functions ofadjustahly prede? er. ningtthe w er level and e pera wh n: usedin juncion-wi h a pr sure' per switch inthe man: ner described-t V 7 Still;another feature ofi thisrinvention resides in the provision of afilll'.control unit having a pair of coaxial Zt ll teraop atins shafts neofwhich, p ovides fonc n l ol of a atei. t mp r ureselec ing switch andsteamer. Qt whi h p ovides for adiustm nt of, the statioik arr c n a ioia pressure, sensitive: water le l; sele ng l sttu iemali y wh ch may erea ily a tached tot-a.- mounting bracket on the control unit.

With the ahove, and, other objects in viewwhich will pn a: a th descripion. P TQQ d this inv nt on resides in; the novel constrtictiqrn,combination, and arrangement off parts substantially as hereinafterdescribed and more particularly definedby the appended claims, it.being; understood that such changes in the precise embodimentoiithe'hereindisclosed invention may be made as come withinthe scope ofthe claims;

The accompanying drawings illustrate two complete 'ex-v amples ot'thephysical embodiments of the invention con-o sli lcted' according to. thebest modes so far -devised -for the practioal application'ofitheprinciples thereof, and in Whl 7. V

Elglljffig l is a-view partlyin side: elevation and 'partly=seetiontane; illustrating the: control unit of'thi's inve'matt-aehedt'tor a: pressure: operated switch a positionto efiectadjustment of the stationary contact of the-- wi ks:

Figp 2:;is, ai crosstsectional view"taken-on -the-plane Qt he-li ezkzt eisu Figure 3 is a perspective view of the control unit of this inventiondetached from the pressure operated switch instrumentality;

Figure 4 is a plan view of the control unit of this invention modifiedby the incorporation of a pair of water temperature controlling switchesand shown in position on a pressure operated switch; and

Figure 5 is a side elevational view of the modified device shown inFigure 4 but with portions thereof broken away and shown in section.

Referring now more particularly to the accompanying drawings in whichlike numerals indicate like parts throughout the several views, thenumeral 5 designates generally the control unit of this invention shownin position upon a pressure operated switch instrumentality 6 to governthe operating characteristics of the switch.

The installation shown in Figures 1 and 2 is the same as that disclosedin the joint copending application of Edgar M. Soreng and Irving Gebel,Serial No. 298,873, filed July 14, 1952, now Patent No. 2,720,564, andthe control unit 5 of Figures 1, 2 and 3 comprises the divisible subjectmatter of said joint copending application. Also reference may be had tothe latter for a more detailed description of the pressure operatedswitch instrumentality 6.

It will be suflicient to note herein that the pressure operated switchinstrumentality includes a housing 7 comprising a shallow cup-likeinsulative body portion 8 open at its top and a closely fitting metalcover 9 closing the open top of the body portion. A diaphragm 10 ofrubber or other suitable fiexible material extends laterally across theinterior of the housing and has its peripheral portion clamped betweenthe cover and rim portion of the cuplike body, and the diaphragm dividesthe housing into two compartments, namely an upper fluid tightcompartment or diaphragm chamber 11 into which air, water or otherliquid may be introduced through an inlet tube 12 having an orifice 13in its outer end, and a lower switch compartment 14 in which is housedthe switch mechanism 15 that is actuated by the diaphragm.

The switch mechanism 15 is of the snap actuated type and comprises amovable contact blade 16 having a contact point 17 fixed to its free endand movable up and down into and out of engagement with an upper fixedcontact 18 and a lower adjustable stationary contact 19. The movablecontact blade 16 is biased in the direction to normally maintain thecontact point 17 in engagement with the lower contact 19. The contact 19is made adjustable toward and from the upper fixed contact 18 to enableadjustment of the amount of fluid pressure which will be required toactuate the switch, that is, to effect snap actuation of the contactblade in an upward direction to disengage the movable contact from thelower contact 19 and bring it into engagement with the upper fixedcontact 18.

To provide for such adjustment, the lower stationary contact 19 iscarried on the medial portion of a flexible arm 20 which has one endportion 21 thereof anchored to the end wall 22 of the cup-like bodyportion of the housing, and has its free end portion 23 extendingdownwardly through an opening 24 in said end wall 22 and into engagementwith the periphery of a cam 26 at the exterior of the housing andagainst which the arm is biased. This cam forms part of the control unitof this invention, and it is rotatable to efiect either upward ordownward adjustment of the lower stationary contact 19 to thus providefor variation of the amount of pressure imposed upon the diaphragm 10necessary to effect snap actuation of the switch mechanism 15 in thedirection to disengage the movable contact 17 from the lower stationarycontact 19.

The cam 26 of the control unit is fixed on the rear end of a manuallyrotating control shaft 27 supported by a bracket 28 secured to theexterior of the end wall 22 of the housing for the pressure operatedswitch instru: mentality. The bracket 28 is an inexpensive sheet metalstamping having a flat base 29 and upright spaced apart front and rearflanges 30 and 31, respectively, bent from the base to extend to oneside thereof substantially perpendicular to the plane of the base. Theflange 30, of course, is bent from the front end of the base, while therear flange 31 is struck from the intermediate portion of the base to beopposite and parallel to the front flange and to leave an aperture 32 inthe base intermediate its front and rear ends in edgewise alignment withthe cam 26 and through which the free end portion 23 of the arm carryingthe lower stationary contact 19 of the switch mechanism projects forengagement with the periphery of the cam.

The bracket 28 serves not only to mount the control unit on a panel ofan automatic washing machine, but also provides a means for mounting thepressure operated switch instrumentality 6 on the machine. For thispurpose, the bracket 28 is securable to the housing of the pressureoperated switch instrumentality with the flat base 29 of the bracketflatwise engaged with the end wall of the cup-like insulated housingsection 8 of the switch and with the front flange 30 of the bracketdisposed a distance laterally outwardly from one side of the housing ofthe switch, as seen best in Figure l. Spaced holes 34 in the frontflange 30 of the bracket are provided to receive screws or rivets orother fastening means by which the control unit and, hence, the pressureoperated switch instrumentality may be mounted on a panel of a Washingmachine with the entire assembly behind said panel.

The control shaft 27 is journalled in aligned holes 35 and 36 in thefront and rear flanges 30 and 31 respectively, of the bracket forrotation on a fixed axis parallel to the base 29 of the bracket. Theshaft 27 projectsforwardly beyond the front flange 30 and is adapted topass through the panel or wall of the housing of the washing machineupon which the control unit is mounted. A control knob, not shown, maybe secured to the front end of the shaft which may have a flat portion37 thereon for that purpose, so that the shaft and, hence, the cam 26fixed thereto may be readily turned manually to effect adjustment of thelower stationary contact 19 to any one of several positions. Thesepositions of adjustment are determined by novel indexing mechanism,generally designated 38 and which comprises a series ofcircumferentially spaced detent notches 39 in the peripheral portion ofthe cam generally opposite that portion of its periphery which isengaged by the free end por tion 23 of the contact arm, and a detentfinger 40 which is engageable in any one of the detent notches.

The indexing finger 40 is stamped from suitable resilient metal and hasan upturned attaching base 41 by which the indexing finger is secured tothe mounting bracket 28, by having the base riveted as at 42 to thefront flange 30 of the bracket with the base of the finger overlying theinner surface of the flange. The attaching base 41 also serves to holdthe control shaft 27 against axial displacement with respect to themounting bracket 28, and for this purpose, the base has an edge portion43 which enters an annular groove 44 in the control shaft to constitutethe sole means for holding the shaft against axial sliding movement inits bearings and for properly locating the cam 26 with respect to theaperture 32 in the base of the bracket and, consequently, with respectto the free end portion 23 of the contact arm when the pressure operatedswitch is secured to the base of the bracket.

The indexing finger 40 projects rearwardly from the attaching base 41substantially parallel to the control shaft 27, through an opening 46 inthe rear'flange 31 of the bracket, and has a rounded free end portion 47shaped to snugly fit in any one of the detent notches 39 in the cam. Inthe embodiments of the invention shown ear-@8 linlthe drawingsthe-opening 46 is defined by a.notch ppenling .tojthe..outer l edge :of.the. rear. fiangehand "theppposing :sideidEesdfwhich,providehabutments. V As ,a seenibestl in .Eigure 2, the r cam i isg provided i'three'detentnnot'ches eqnispaced tcircumferenti allyatithat ,portion of ,the periphery of the camwhi chlis remote ."fromdhelbase r29 and, more;pariticnlarlmllhef'free end poftiori"23 "of thecontact arm. L'Each :6f :the detent notches is diametrically oppositeraalobeton :the scam, and "these" lobes are radially "spaced differentidistances from ""the akis "of rotation of the" cam. "Withfithe positionof "the 'd'etent mechanism seen in"Figure 2, thewcontact-arm hearsagainst 1a 'lobe "48 wofthe cam whichhhas lleast throw.iUponcounterclockwise rotation of the cam, as 'YiewdI'in. Figurefl,to'bring the. roun'ded freeeridypor- "'tion 47 oftheidetentifin er'intothe middle detent notch, ithetsecorfd lobe 49 'of'the cant 'is'.broughf'to. bear" against the' freeend. offgthe contact arm to position.the: contact "i9c'arrid "thereby' aishort distance closer to"the fixed."stationary' contact 18. :L ikewis further"countereld'ckwisevrotationfirthe "cam to b'rirrgthe lastzde'tent notehM -into 'alignment' with Ithefree endportion of ithe de- Went fingerbrings the "cam lobe *50' efi'g'reates'rthrow to bear upon the freesendpor'tion ofthe *comaerarmwo aposition the adjustable "stationary contactt'carried thereby blosest'to thefixedwontact 18.

Atterition' is directed to the fact that the detent notches "39H1n thecam .are' relatively deep. This assu'resthe'- best rqposible= detent*ac'tion arid tends "to :prevent accidental rotation-bf the controlshaft2f7 b'eyond thedes'i'td set ting tjf the' cam. Asidefromitsfunbtionofarre's'tirj ig rota'tion' bfthe controlshaft at thedifierent'defindf'po- ""sitions-fif -a'djustment-'o't the contact arm20,?the *detent fi-ngers also serves to define 'the limits-of rota f"the cont-r61 shaft. "To'=this"end, "SIOP'Z abutmentsi s VidCdOIY-dhccam -at"those sides of the two rem'tite detent notches 39 which are"adjacent to'the' nnnotchedfperiiihery mf the=cam5for engagementwith thesides "of the rotlnded free -erid -portion of the indexin'g finger.

MAS stated, it is highly desirable to :provide "a prononnced detentaction through 'the 'provis'ionofi relatively :deep detent notches inthe cam and"'-toerni7loy*the'detent finger asa means of limitingrotation an the control shatt. *However, this introduces a "seriousproblem whieh 'restilts from the necessity-of "forming the iridex fingerof relatively light weight highly resilient-"material :lto renable 1 the-same -to be 'fl'exdi a '-"snbs'tan'tial amount haw-aw from the axis ofthe' control ehaftdui'ing thetimes sitnpa'ssestioven the" teethbetween*the=-detent ot ches. 'It his; essential c'of course, 1 that "thedetent finger have silhrstantial; length ias well *as a com arativelylight *cro'ss szsecti'onstoafacilitate fiexure of 'the finger wvhen thecam is rotated to Zdifierentse'ttings. 'BecanSe 'ofttheQe requirements,however, the index finger is substantially meakmndineapable ofwithstariding the snb'stantiallateral tWisting' fomeswhiCh may beapplied thereto dni'ingwotalion- 'f the carn from'one positiontoandthefbfitfmdre especially, at such times *as whenfit" is "engagedinfi'th'er one of the remote detent notches ==arid :an operator ofthe"mach-ine acci'dentally tries to rotate.thefshiftijin'the"'wrongdirec'tion. This wouldbe comparable toapfilying a'forceto'thecontrol shaft in a direction terfding tolrotate the cam in'the clockwisedirection seeninZEigure 2,Ybeyorfd 'thelimitof rotation established bythe engagement fthe detent finger withtheabutment 51 on the cam at-thattime. s

"The control knob ordinarily mounted on the bitter "en'dofthe controlshaft isrelatively. largein Hiame'ter, asis well known, and the operatormay applytst'lbstan- "tiaYtor u'e thereto which, .if applied inthe'wrongdirectiom'would' twist'the index finger edgewise, in a 'difection"sl'ibstantially parallel to the control shaft. This easilylead f'todeformation or breakage "of'theiridx finger.

I 11 t riswone-Jof the .it'eatures --.of .uthisl invention thaty prof.ttectiori'-is..affordd againstrsuchflamage tojthe inder finger 'by areason of vthe Zfabt a portion ltliereof tclo sely adjacent to .itsouter! freerv end' is received: ingi the; opening -t 5 eonnotchl46 in.therearfiangeBLofQthe mountings-braeket. "This notch has snfiicientdepthfin atdirection p er'pendicillar i tothe controlwshaf t toaccommodatealls of the "reqni red Iflexing motion of .-the irideX-:fi g-vThe *Width :i li notch, t however, I is such ithat [the =iridex fingerwill Pbe brought .into engagement with one .jside mor the other ofthetnotch whenever thef finger isflexd edgewise, either hasra resilltelf normal rotationof-rthe cam or. by an operator .uhknovvin'glyattempting to rotatel thefshaftlbeyond one of t its'ltlimits, L toAhus raosi tively preclnde deformation of -15 ordarnage to theffingert l ,Thecontrol unit -thus Ifar describ d is nsefnl only to efiect adjustment rfthe leveliof washing liqnid reqnired tolbel introducedt-into the tirb ofan ailtomatic washing .Tma'chine, Other lswitchiainstrumentalitiesseparate: from .the control innit .asawell. as the pressuretswitch.mustibe emiiloy'd to control the. temperature of'lthe waterused.to lfilllthe machine. v 7

However, water temperature 1controlling.switchlinstruement'a'lities. maybe 1- incorpdratd int the controlannit .'so tum Itheilatter thenlbecomesibotm a water'. level and .Water' temperature controlling fdevice. QSnch;a control v.uf it {isjillnstratedeinfFigures -4 1ari'd'f5 .of. thedrawings, arid the specific con'struc tionanti arrangement Eat .the 7temperature controlling; Switch mechanismfshown' in 'theseifiguresf'is"frilly Tdisclosed and claimd in my coperiding.applicationfserial1N0. 463,7s's,iffi1dJanuar 13,1934. -...As"willappearlin greater ."detgil hereinafterQ it -is'a i feature ofthefdnakpnrposecontrol instrumn'tality shown iiinfi i ures 4 andtS thatthe. selection. f 'ater' tnipei'a'tnres aridlvlsisfshnfrlifiedfthrodgh'lthefpfovi'sion;ofloprating shftsTor each-.6 il'leifi'sfrtlmb'ntafiti s which'sha ftsfalife telescoped onew1thinltheEther. FThebiitr =-lift"'53 co'ntr6ls fthe switching .ncssaffy "for Iselection "of "the temperature of the "water u'sdfio'ifillttlieifia hihfi-ile 40 thefihnershft '27'fpov'ide'sif6r a tistmeht bfjthe pressnredfstifitch. IIt'I iiG St tance above and facing the terminal head. Therivets '57 at the opposite end of the terminal head provide for contactblades extend beneath the control shaft and their free end portions liebeneath and are cooperable with the stationary contacts 60 on thecontact clips 59. The contact blades 61 are preferably biased upwardlyinto engagement with the contacts 60 except when cammed downwardly awayfrom their respective stationary contacts, in consequence of rotation ofthe outer shaft 53.

The operating shaft assembly which comprises the outer and inner shafts53 and 27, respectively, is rotatably carried by the mounting bracket inbearings 62 and 63 formed in the front and rear flanges, respectively,of the mounting bracket. These bearings support the two shafts forrotation on a common axis substantially normal to the flanges and spaceda distance above and parallel to the plane of the base of the bracketsufficient to accommodate the temperature selection switch 54 beneaththe operating shaft assembly. The outer shaft 53, of course, is oftubular construction and has an inner section 64 comprising the rotor ofthe temperature selector switch, and a coaxial front section 65, ordriver, slightly smaller in diameter than the rotor.

The inner section or rotor 64 is comprised of insulating material andits length is such as to closely fit between the front and rear flangesof the mounting bracket. In addition, the rotor sleeve 64 has a rotationtransmitting connection with the front section 65 of the outer shaft,which connection may be provided by a non-circular rear end portion 66on the driver engaging in a similar noncircular counter bore 67 in thefront of the rotor. The forward sleeve or driver 65 of the outer shaftmay conveniently be made of metal and it passes forwardly through thefront flange 30 of the bracket to be rotatably accommodated in thebearing 62 thereof and to have its forward extremity accessible formanual actuation, as by a knob or the like, not shown, attached thereto.

The inner shaft 27' is rotatable inside the outer shaft and projectsthrough both flanges of the mounting bracket. Its forward extremityextends slightly beyond that of the outer shaft to be accessible formanual actuation by a suitable control knob thereon, not shown, whileits rear extremity projects a distance beyond the rear flange of thebracket and has the control cam 26 fixed thereto. The bearing 63 in therear flange 31 of the bracket rotatably receives and supports the rearend portion of the inner shaft. Consequently, rotation of the innershaft 27' effects adjustment of the contact arm 20 of the pressureswitch in the same manner as that described heretofore with rotation ofthe inner shaft being arrested at each setting of the shaft by theengagement by the outer end portion of the detent finger 40 in any oneof the detent notches of the cam 26. In this case also, the detentfinger has a portion adjacent to its rear end slidingly received in anotch 46 in the rear flange of the bracket opening to its outer edge toprevent damage to the index finger which would otherwise result from thesubstantial twisting force applied thereto during rotation of the cam orat the limits of rotation of the inner control shaft 27'.

While the insulating sleeve or rotor 64 of the water temperature switchis held against axial motion relative to the mounting bracket by itsconfinement between the front and rear flanges of the mounting bracket,it is necessary to provide a retainerv for the outer section or driver65 of the shaft 53. The retaining means for the driver comprises theplate-like base 41 of the index finger which is fixed to the innersurface of the front flange 30 of the mounting bracket and. has an edgeportion entering an annular groove 68 in the exterior of the driver. tolock "the same against'axial' motion in its bearing'62.

. It will be understood, of course, that the edge portion of the base ofthe index finger which enters the groove in the driver may be providedby the bottom and sides of a notch formed in the base of the finger andopening to its edge remote from the finger, so that the base of thefinger substantially straddles the driver in a manner described atgreater length in my aforesaid copending application, Serial No.403,755.

The inner shaft 27 is held against axial motion relative to the mountingbracket by a bifurcated retaining plate 69, confined between the rearflange 31 of the bracket and the adjacent rear end of the rotor 64, withthe legs of the plate straddling the shaft 27 and engaging in an annulargroove 70 therein. It is a feature of the control unit shown in Figures4 and 5 that the notch 46 in the rear flange of the mounting bracketwhich steadies and reinforces the index finger against lateraldeformation is provided by striking a tab 72 forwardly from the outeredge portion of the rear flange. The tab 72 thus formed projects into anarcuate recess 73 in the adjacent rear end portion of the rotor 64, tohave engagement with circumferentially spaced abutments 74 at the endsof the recess to thus limit rotation of the outer shaft.

The specific switch mechanism 54, the manner in which rotation of theouter shaft effects opening and closing of the switches, and the detentmeans for arresting rotation of the outer shaft at these differentswitch on and off positions, all are features which are claimed in mycopending application, Serial No. 403,755, and form no part of thisinvention. Reference may be had to my aforesaid copending applicationfor a detailed disclosure thereof.

It is suflicient to note that one contactor 61 and its cooperatingstationary contact 60 controls the energization V and deenergization ofthe electromagnetic valve in the hot water supply line for the washingmachine, while the other contactor and its cooperating stationarycontact 60 conaccompanying drawings, it will be readily apparent tothose skilled in the art, that this invention provides a control unitfor automatic washing machines and the like which features detentmechanism of exceptional simplicity and ruggedness and which has thefurther advantage of being capable of manufacture at a low cost.

What I claim as my invention is: 1. In an instrumentality of thecharacter described a combination mounting structure and indexingmechanism,

comprising: a stamped and formed bracket having opposing spaced apartfront and back walls; means on the front wallproviding for thesecurement of the bracket to a support, said front and back Walls havingaligned holes; a control shaft journalled in said holes; a cam on theshaft near the rear bracket wall and having detent notches; a resilentindexing finger having an attaching base; the control shaft having acircumferential groove of a size to receive a marginal edge portion ofthe attaching base;

and means securing the attaching base of the indexing finger to thefront wall of the bracket with said marginal edge portion of theattaching base engaged in the circumferential groove in the controlshaft to thereby secure the shaft against axial displacement and withthe indexing finger extending rearwardly lengthwise of the shaft andhaving its free rear end portion bearing resiliently against the cam tocoact with the detent notches therein.

2. A' control unit of the character described comprising: a mountingbracket having a flat base and'sp'aced apart front and rear flangesprojecting from the base; an operating shaft rotatably supported by saidflanges and having a rear portion projecting behind said rear flange anda portion projecting in front of the front flange to be accessible formanual manipulation; a cam on the projecting rear portion of said shafthaving a plurality of circumferentially spaced notches in its periphery;and a resilient finger carried by the front flange and extendingrearwardly lengthwise of the shaft to have its rear end portion engagein said notches in the cam to cooperate therewith in providing detentswhich define the positions of the cam, said finger being flexible towardand from the shaft and being steadied against distortion transversely toits direction of fiexure by having a portion thereof received betweenthe opposed edges of an opening in the rear flange.

3. A control unit of the character described comprising: a mountingbracket having a flat base and spaced apart front and rear flangesprojecting from the base; an operating shaft rotatably supported by saidflanges at a location to one side of the base and having a portionprojecting beyond one of the flanges to be accessible for manualmanipulation; a cam on said shaft near the rear flange having aplurality of circumferentially spaced notches in its periphery; aresilient finger carried by the front flange and extending rearwardlylengthwise of the shaft with a portion of said finger spaced from thefront flange flexible toward and from the shaft and engaged in thenotched periphery of the cam to cooperate therewith in providing detentswhich define the positions of the cam; and means for steadying saidfinger against distortion transversely to its direction of fiexurecomprising a pair of opposite abutments on the rear flange between whicha portion of said finger is guidingly received, said abutments beingspaced apart a distance substantially equal to the width of said portionof the finger and extending substantially parallel to the path offiexure of the finger and comprising the opposed edge portions of anopening in the rear flange.

4. A control unit of the character described comprising: a brackethaving a pair of front and rear supporting members in fixed spaced apartrelationship; manually rotatable actuating means conjointly carried bysaid supporting members; a cam on said actuating means near the rearsupporting member having a plurality of circumferentially spaced notchestherein; a resilient finger carried by the front supporting member andextending rearwardly therefrom toward the cam with a rear portion ofsaid finger flexible toward and from and engaged with the notchedportion of the cam to cooperate therewith in providing detents whichdefine the positions of the actuating means; and means for steadyingsaid finger against distortion transversely to its direction of fiexurecomprising a pair of opposite abutments on the rear sup porting memberbetween which a portion of said finger is received, said abutments beingspaced apart a distance substantially equal to the width of said portionof the finger and extending substantially parallel to the path 10 offiexure of the finger and comprising the opposed edge portions of anopening in the rear supporting member.

5. The control unit of claim 4 wherein said resilient finger projectsrearwardly from a plate secured to said front supporting member to mountthe finger, and wherein an edge portion of said plate is engaged in acircumferential groove in said rotatable actuating means to precludeaxial displacement thereof.

6. A control unit of the character described comprising: a mountingbracket having a base and spaced apart front and rear flanges projectingupwardly from the base, said rear flange having a notch opening to oneside thereof provided by a tab bent forwardly out of the plane of therear flange; an operating shaft assembly rotatably journaled in saidflanges and including a tubular outer shaft having an arcuate notch atits rear defining circuferentially spaced abutments on the outer shaftwhich engage said tab to define the limits of rotation of the outershaft, and a coaxial inner shaft rotatable inside the outer shaft, oneend portion of the inner shaft projecting rearwardly beyond the adjacentend of the outer shaft and terminating behind the rear flange, and theother end portions of said shafts projecting forwardly through the frontflange so as to be accessible for independent manual actuation from alocation ahead of the front flange; a cam on the rearwardly projectingportion of the inner shaft having a plurality of circumferentiallyspaced notches in its periphery; and a resilient finger carried by thefront flange and extending rearwardly over the shaft assembly to haveits rear end portion engage in said notches in the cam to cooperatetherewith in providing detents which define the positions of the cam,said finger being engaged in said notch in the rear flange to besteadied by the opposed side edges thereof against distortiontransversely to its plane of fiexure in consequence of sideward forcesimposed upon the finger upon rotation of the cam from one of itspositions to another.

7. The control unit of claim 6 further characterized by the provision ofrotation stops on the cam at the circumferential ends of the notchedportion of its periphery, engageable with said resiliently flexiblefinger to define the limits of rotation of the cam.

8. The control unit of claim 6 wherein said resilient finger projectsrearwardly from a flat plate substantially perpendicular to the finger;and wherein said flat plate is secured flatwise to the front flange,with an edge portion of said flat plate engaged in a circumferentialgroove in the outer shaft to prevent axial displacement thereof.

References Cited in the file of this patent UNITED STATES PATENTS1,887,878 Smith Nov. 15, 1932 2,636,093 Clark Apr. 21, 1953 FOREIGNPATENTS 135,751 Australia Dec. 23, 1949

